Continuous smelter



Dec. 6, 1955 H. BROWN I 2,726,078

CONTINUOUS SMELTER Filed Feb. 8, 1954 2 Sheets-Sheet i Dec. 6, 1955 H, BR 2,726,078

CONTINUOUS SMELTER Filed Feb. 8, 1954 2 Sheets-Sheet 2 J7 INVENTOR.

United States Patent CONTINUOUS SMELTER Harold Brown, Denver, Colo., assignor to Precious Metals Refining Company, Denver, Colo., a common law trust of which Karl A. Sparks is executive trustee Application February 8, 1954, Serial No. 408,864

6 Claims. (Cl. 266-17) This invention relates to a smelter for continuously smelting metal-bearing ores and mill concentrates, and has for its principal object the provision of a smelter through which a continuous stream of ore or concentrates can be fed, and which will efliciently act to continuously remove the metallic values from a stream of ore and concentrates and continuously discharge the undesirable slag.

Another object of the invention is to provide means in a continuous smelting device for obtaining a continuous gravity separation between a plurality of diiferent metals so that a metal classification can be obtained simultaneously with the removal of the metals from the slag.

Other objects and advantages reside in the detail construction of the invention, which is designed for simplicity, economy, and efliciency. These will become more apparent from the following description.

In the following detailed description of the invention, reference is had to the accompanying drawing which forms a part hereof. Like numerals refer to like parts in all views of the drawing and throughout the description.

In the drawing:

Fig. 1 is a vertical section through the improved smelter, taken on the line 11, Fig. 2;

Fig. 2 is a horizontal section, taken on the line 2-2,

Fig. 1;

Fig. 3 is a similar section, taken on the line 3-3, Fig. 1; and

Fig. 4 is a detail view, illustrating a type of metal condenser employed in the smelter for recovering vaporous metallic values.

The improved smelter comprises a vertical cylindrical smelting chamber 10 in which a vertical rotatable agitator shaft 11 is axially supported in suitable bearings 12. The agitator shaft is provided with a plurality of inclined agitating arms 13 adapted when rotated to exert an agitating and elevating eflect on the contents of the smelting chamber 10. The agitator shaft 11 is constantly driven in any desired manner, such as through the medium of worm gearing in a worm gear housing 27 rotated from a suitable belt pulley 28.

The ores or concentrates to be smelted are fed from a suitable storage bin 14 through a feed chute 15 to a downwardly inclined conveyor tube 16 which opens to the smelting chamber 10 approximately one-third the length of the latter above the bottom thereof. The conveyor tube 16 is, provided with any suitable screw or scroll conveyor 17 driven in any suitable manner, such as through the medium of worm gears in a housing 18 driven from a drive pulley 19. A slag passage 29 communicates from the upper extremity of the smelting chamber 10 to a vertical slag chamber 30 terminating at its bottom in anysuitable slag chute 31. A bottom discharge 43 is provided in the smelting chamber and an overflow tap 32 opens from the smelting chamber 10 below the slag passage 29.

The smelting chamber 10 is completely surrounded by 2,726,078 Patented Dec. 6, 1955 ice a cylindrical heating jacket 20 which opens at its bottom to a hot gas chamber 21 to which hot air or hot gases are continuously fed through a hot gas flue 22 from any suitable source. A vertical flue tube 23 conducts the hot gases from the jacket 20 to any suitable discharge stack 24. The flue tube 23 extends through a vertical cylindrical gas dome 25 which is open at its bottom to the smelting chamber 10 and closed at its top by means of a top plate 26.

The heating jacket 20 is preferably surrounded by fire brick 41 or other suitable insulation. The hot gas flue 22, the slag chamber 30, and the gas dome 25 are also suitably insulated by means of suitable heat insulation 42.

A plurality of vertically spaced vapor taps 33 open from the gas dome 25. Suitable vapor conduits 34 extend from the vapor taps 33. Each vapor conduit 34 terminates in a condenser as shown in Fig. 4. The condensers comprise sealed fluid containers 35 filled with water or other suitable chilling fluid 36. The containers are hermetically sealed by means of suitable sealing caps 37 and are provided at their bottoms with discharges 38 controlled by means of suitable gate valves 39.

One of the condensers is provided for each of the vapor pipes 34. The latter pipes extend through the caps 37 of their respective condensers, and are sealed thereto in any desired manner, and terminate below the fluid level therein. A vacuum line 40 also communicates through each cap 37 and is sealed thereto. The vacuum lines are connected to any suitable vacuum pump so as to constantly maintain a partial vacuum in the containers 35 above the fluid level therein.

Operation Let us assume that the vacuum pump connected to the condensers, the agitator shaft 11, and the conveyor 17 are operating, and that hot gas is being forced through the gas flue 22 into the gas chamber 21, upwardly through the jacket 20, the tube 23, and out through the stack 24.

The ores or concentrates to be smelted flow down the feed chute 15 and are forced into the bottom of the smelting chamber 10 by the action of the scroll conveyor 17. The speed of the latter is regulated to obtain the desired volume of flow. The heat melts the metallic values from the ores and concentrates, causing a pool of molten metal to accumulate in the bottom of the smelting chamber 10. The molten metal together with the elevating action of the agitators 13, forces the lighter non-emtallic gangue upwardly in the smelting chamber until the slag overflows through the slag passage 29 and falls by gravity through the slag chamber 30.

The molten metals gradually build up in the smelting chamber 10 and stratify by gravity until the lightest metal present overflows through the overflow tap 32. The heavier metals may be discharged at intervals to maintain the proper level in the smelting chamber through the medium of the discharge 43. 7

Certain of the rare metals present, having low melting points, will vaporize and rise into the gas dome 25, where they will stratify in layers due to the diiferences in their specific gravities. The layers are tapped oil through the vapor taps 33, thence through the vapor tubes 34 to their respective condensers, where the respective metal vapors will be condensed in the chilling fluid in the containers 35 and discharged at intervals through the gate valves 39.

The molten metal is prevented from rising in the conveyor tube 16 by the downwardly acting pumping action of the conveyor and the descending column of chilled ores and concentrates.

The slag chamber 30 extends downwardly alongside the smelting chamber 10 to form a gas trap at the top to prevent gas and vapors from flowing from the smelting 3 chamber. The action of the vacuum pump draws the gases into the dome 25 and causes the gases to bubble through the water or other solution in the containers so that loss of valuable vapors is prevented.

While a specific form .of the improvement has been described andillustrated herein, it is to be'understood that the same may be varied, within the scope of the appended claims, without departing from the spirit of the invention.

Having thus described the invention, What is claimed and desired secured by Letters Patent is:

1. A continuous smelter comprising a vertical smelting chamber having an ore admission opening adjacent the bottom thereof; continuously operative means for conveying a continuous stream of metal-bearing ores and forcing the same into said opening; a rotary agitator mounted in said chamber and provided with agitating means disposed so as to urge an upward movement of the ore in said chamber; means surrounding said smelting chamber adapted to supply heat for smelting the ore therein; a slag overflow outlet leading from thetop of said smelting chamber; a molten metal discharge outlet at the bottom of the smelting chamber; and an outlet for a lighter molten metal component disposed at a point intermediate the top and bottom of the smelting chamber so that Stratified liquid molten metal components of different specific gravities may be separately discharged.

2. A continuous smelter as described in claim 1 having a slag chamber positioned to receive the overflowing slag, said slag chamber being positioned alongside said smelting chamber and being sealed at its top to form a gas trap.

3. A continuous smelter as described in claim 2 having a vapor dome arising from and communicating with said smelting chamber; and a plurality of vapor taps communicating from said vapor dome at vertically spaced intervals.

4. A continuous smelter as described in claim 3 having means for individually condensing the vapors flowing from each of said vapor taps.

5. A continuous smelter as described in claim 4 having a heating jacket surrounding said smelting chamber r for transferring heat to the latter; and a hot gas flue arising from said heating jacket through said vapor dome.

6. A continuous smelter as described in claim 5 having a molten metal overflow extending from said smelting chamber adjacent the top thereof; and a discharge communicating with said smelting chamber adjacent the bottom thereof.

References Cited in the file of this patent UNITED STATES PATENTS 1,887,286 Buskett Nov. 8, 1932 1,961,425 Maier June 5, 1934 2,051,962 Mitchell Aug. 25, 1936 2,430,389 Chubb Nov. 4, 1947 

1. A CONTINUOUS SMELTER COMPRISING A VERTICAL SMELTING CHAMBER HAVING AN ORE ADMISSION OPENING ADJACENT THE BOTTOM THEREOF; CONTINUOUSLY OPERATIVE MEANS FOR CONVEYING A CONTINUOUS STREAM OF METAL-BEARING ORES AND FORCING THE SAME INTO SAID OPENING; A ROTARY AGITATOR MOUNTED IN SAID CHAMBER AND PROVIDED WITH AGITATING MEANS DISPOSED SO AS TO URGE AN UPWARD MOVEMENT OF THE ORE IN SAID CHAMBER; MEANS SURROUNDING SAID SMELTING CHAMBER ADAPTED TO SUPPLY HEAT FOR SMELTING THE ORE THEREIN; A SLAG OVERFLOW OUTLET LEADING FROM THE TOP OF SAID SMELTING CHAMBER; A MOLTEN METAL DISCHARGE OUTLET AT THE BOTTOM OF THE SMELTING CHAMBER; AND AN OUTLET FOR A LIGHTER MOLTEN METAL COMPONENT DISPOSED AT A POINT INTERMEDIATE THE TOP AND BOTTOM OF THE SMELTING CHAMBER 